Measurement of thermal conductivity and specific heat
June 24, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3672205 3821895 3913379 Heat meters Bridge circuit with drift compensation Bridge circuit arrangement for a gas detection instrument Multicomponent thermal conductivity analyzer Modulated fluid detector Method of and apparatus for nondestructively determining the composition of an unknown material sample Dynamic current drive method for powering thermal conductivity detectors InventorsAssigneeApplicationNo. 210892 filed on 06/24/1988US Classes:702/136, Thermal related property73/25.03, Thermoconductivity73/204.16, By control of a separate heating or cooling element73/204.17, With distinct heating circuitry for a self-heated sensor374/30, By differential temperature measurement along undisturbed thermal gradient374/44, Thermal conductivity702/30Chemical property analysisExaminersPrimary: Teska, Kevin J.Attorney, Agent or FirmInternational ClassesG06F 015/20G01K 017/08 AbstractA method and apparatus for determining both the thermal conductivity, k, and specific heat, cp, of a fluid of interest are disclosed. An embodiment uses proximately positioned resistive heater and thermal sensor coupled by the fluid of interest. A pulse of electrical energy is applied to the heater of a level and duration such that both a transient change and a substantially steady-state temperature occur in the sensor. The k of the fluid of interest is determined based upon a known relation between the sensor output and k at steady-state sensor temperature; and cp of the fluid of interest is determined based on a known relation among k, the rate of change of the sensor output during a transient temperature change in the sensor and cp.Field of SearchIncluding digital or pulse measuring circuitryIncluding detail of feedback or rebalancing circuitry By control of a separate heating or cooling element With distinct heating circuitry for a self-heated sensor Thermoelectric junction Resistive element With substrate carrier (e.g., thin film) DETERMINATION OF INHERENT THERMAL PROPERTY (E.G., HEAT FLOW COEFFICIENT) Thermal conductivity THERMAL CALIBRATION SYSTEM HEAT FLUX MEASUREMENT With combustion engine By thermoelements connected in series opposition At plural zones | |
